fpb111

Barn996
It was a 60. We put a Datsun 2.0ltr OHC engine in it while stationed in SanDiego in 69. The Jags were mine the Sprite was my friend Larry's.

BruceP

You'd also lose that nice ride you got with the new shocks. When the car is lowered this way, it will eat up some of the available shock travel. That first bit of travel in a gas shock is the most compliant. Because gas has a natural rising spring rate, it gets firmer as it's compressed.

So, basically, in addition to the problems cited above, you'll lose the benefit that you started out wanting in the first place.

My vote is with those who say that shocks and springs should be matched. In all likelihood, a proper setup will give you a better ride than what you're contemplating anyway.

EastBay

yep, only on the Porsche forum do you hear them scream "OMG YOU CANNOT DO IT" in the meanwhile the real world moves along. The only real problem is the trial and error of cutting small amounts of coil and the labor of reinstallation to get the proper height you want. I'd recommend 1/8 of a coil turn or less per initial cut.

If you can document the drop per coil cut it would be super useful information to the forums.

Pac996

Good thing I checked the end of this thread where you touch on reality.

Since the spring compresses cutting a half inch off will end up being more than a 1/2" drop. This is besides being the wrong thing to do with a 911 that has tight enough tolerences already.

Ray S

How do you cut these (especially the rears) and make them work as intended?



E-bay is littered with ads for Eibach, H&R, and other 996 springs for under $300 bones. This would be a much better way to go for hardly any money IMHO.

http://cgi.ebay.com/ebaymotors/EIBAC...Q5fAccessories

Torontoworker

Ahhh, you people are all **** - how low is too low? (Your too low when you start forest fires??)
http://www.youtube.com/watch?v=MzTMo...eature=related

Then there is the questionable concept of less (no shock oil?) is more...
http://www.youtube.com/watch?v=C8Kw5jiwhv4

nick49

Cutting a spring will increase the stiffness, see my post #19. Imagine a torsion bar suspension. A long bar is held fixed at one end and the other is attached to a movable link, A-arm, etc. Usually one would increase the diameter to increase the spring rate, another way is to shorten the overall length and keep it the same diameter. I believe the spring rates are progressive, that is, the more the rod twists the resistance continues to increase as well. The overall length can contribute to how linear and how much travel the spring will have.

Another good example of this is adjustable anti-sway bars on our cars. I'm thinking of the 3 hole adjustable type. The bar is just a torsion spring really. Mounting it so the overall length is the longest yields the softest ride, conversly the shortest length the firmest. The diameter is constant, the difference in lengths makes the difference in resistance.

Use the same spring steel rod of the same diameter, one is 6' long, one is 5' long. Roll both lengths into coils 3" in diameter. The shorter coil will be significantly stiffer than the longer.

soverystout

Plainly, the answer is you don't. Now if your talking about a 73 Plymouth duster, well then yeah you can cut the springs and make it into a bigger POS.

The OP mentioned that he saw Chip Foose cutting springs on Overhaulin. Most likely the car was late 60s to early 70s muscle that did not have a very advanced suspension system. Hell, it most likely had leaf springs in the back.

EastBay

Actually, I think you mean the front as the back is the standard spring. Looks like you have a little bit to cut off the top - 1/4 turn and maybe some off the bottom another 1/4 to 1/2 turn. Either way looks to be more than enough for a drop.

I do agree it is much easier to just buy what you want for springs these days, but if you are more adventurous it sure looks doable to me.

dallison28

the problem you will prob have is, the ends of the spring are designed as suck to sit and rest for a safe fit/ride. I would think that you would have to bend and chop $20 of the spring to get it close to right.

The openings a the top and bottom of the spring need to be a certain width to fit properly. I don't think this would be safe to do on a dd. If it's going on a track, i wouldn't trust modified springs.

Shark Attack

Chopping stock springs

Sounds like a vacation desination.

goliver

Don't know the phisics of why other than the linked posts which seem logical enough. I can tell you from real world experience of having lowered many Silverado and other trucks from the 80s, 90s to current ones, cutting springs makes em stiffer for sure. The real trick is matching shock valve rate with spring rate. Without the shock/spirng dynos (i think they are called) to measure it is guess work for sure.

Not a biggie for sure if you miss the best setup, but would be hard to get the same results that the Porsche engineers get with all the testing they do. For fifty bucks why not take Ivangenes springs giver a go and post up the reults. At the end of the day it is just a car. Your car. Do what you want. BTW, you don't have to heat the bejeezus out of the springs to cut em.

Barn996

Like Seven Springs?

ivangene

4Scargo

I toyed with the idea of chopping springs. It's old school.

Another old school trick was to heat them up and collapse them to the length you wanted. They may lose tensil (sp) strength and become brittle and break. (I heard of someone welding on the little step on a Cessna 172 spring landing gear that eventually broke, OMG)

But, old school again, you can heat them up with an electric welder compress them to the height you want. If you do do it, let us know.


(or you can buy some used H&R's for about $200 and do it the "right" way)